ContribDieselFoamInjectorPropertiesInjectorType

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Options:

• commonRailInjector
• definedInjector
• multiHoleInjector
• swirlInjector
• unitInjector

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The main difference between the different injector types is how the velocity is calculated. The velocity can either depend on the pressure inside the domain, or be completely pressure independent.

• commonRailInjector

Velocity is calculated from the injectionPressureProfile according to

$U = \sqrt{\frac{2(P_{inj}-P_{amb})}{\rho}}$

where $P_{amb}$ is the average pressure in the computational domain and

updated at each injection.

• definedInjector

The velocity is given in the velocityProfile.

• multiHoleInjector

Velocity is calculated the same way as for the unitInjector.

• swirlInjector

Identical to commonRailInjector.

• unitInjector

Velocity is calculated from the massFlowRate profile according to the formula

$U = \frac{\dot m}{\rho C_D A}$

where A is the injector-orifice area.

The injection pressure (written at the start) is never used but serves as valuable information.

It is calculated according to

$P_{inj} = P_{amb} + \frac{1}{2}\rho \left( \frac{m_{inj}}{C_d \rho A (t_{eoi}-t_{soi})} \right)^2$